Time control device



March 18, 1952 Filed Sept. 13, 1949 J. A. DARWIN TIME CONTROL DEVICE 2 SHEETS-SHEET l INVENTOR. tlsep/z A. fiaz'wzkz ATTORNEY March 18, 1952 Rw 2,589,995

TIME CONTROL DEVICE File d Sept. 13, 1949 2 SHEETS-$HEET 2 INVENTOR. l zla seya A, Darn 1::

ATTORNEY Patented Mar. 18, 1952 UNITED STATES PATENT OFFICE TIME CONTROL DEVICE Joseph A. Darwin, South Orange, N. J. Application September 13, 1949, Serial No. 115,327

8 Claims, 1

Pursuant to the instant invention, there is provided a time control device such as a. defroster unit for refrigerators having two cooperative controls which may be conveniently set forthe purposes herein mentioned. The unit enables the user to set the time at which the refrigerator will be automatically defrosted and the defrosting interval, in a given predetermined time cycle, for example, in each twenty-four hour time interval.

These and other advantageous objects, which will later app-ear, are. accomplished by my invention, of which some of many possible forms are shown in the drawings and hereinafter-more particularly described.

In the drawings:

Fig. 1 is a perspective view of a switch, motor and motor, driven shaft to which the invention is adapted to be applied,

Fig. 2 is an enlarged, fragmentary, elevational view, taken on line 22 of Fig. 1,

Fig. 3 is a. perspective view of a shaft extender tube adapted to be secured to the motor shaft,

Fig. 4 is a perspective view of a time-setting member adapted to be secured to and normally rotate in unison with the shaft extender tube,

Fig. 5 is a perspective view of a cam member,

Fig. 6 is a plan view of the time-setting member of Fig. 4 with the cam member of Fig. 5 shown secured thereto,

Fig. 7 is an elevational view of an interval member embodying my invention,

Fig. 8 is a plan view thereof, taken on line 8-8 of Fig. 7,

Fig. 9 is a schematic view of the cam shown displaced radially so that the outer cam surface thereof will engage and displace the switch lever on rotation of the time setter, for a prolonged interval,

Fig. 10 is a similar view, showing said parts in a position wherein the cam is not appreciably displaced by the interval setter,

Fig. 11 is a perspective view of an assembled timer unit embodying the invention,

Fig. 12 is an elevational view showing the timer unit of Fig. 11 secured to the motor switch unit of Fig. 1,

Fig. 13 is an elevational view of the invention embodied in casing, and

Fig. 14 is a top plan View thereof, taken on line [4-44 of Fig. 13.

The defrosting timer of my invention is adapted to be used in connection with a shaft completing a predetermined time cycle at each revolution; for example, the-shaft 20, drivmay conveniently extend from the casing 3! enclosing other and associated parts of the device hereinafter described, said knob having a pointer as which may be brought to registry with any point on the time setter dial 38 fixed to the casing 3'1. By this arrangement, the timer unit will defrost the refrigerator whose electric circuit it controls at the hour set by the pointer during each time cycle covered by a revolution of shaft 29. Thus, if shaft 20 rotates once per twenty-four hours, the refrigerator will be automatically defrosted at the same time each day.

In addition thereto, the invention provides an automatic defrosting interval control, hereinafter described and one form of which is shown in Figs. 7, 8 and 11, including an interval pointer 39 for registry with interval markings (for example, 2, 3, 4, shown in Fig. 11, 2-3 inclusive shown in Fig. 14) on the interval face 40 of knob 36.

The invention may be used to provide a defroster time control of the electric circuit of the refrigerator in any desired or convenient manner. For example, the unit may be used to open any desired or convenient switch 43 which normally closes the circuit of a plug 4! (for connection to a wall or other outlet) and an outlet 42 on the casing 31, to which the refrigerator plug may be secured. It will be appreciated that the timer of the invention herein described may be used to control the opening and closing of any other desired or convenient type of switch. The switch shown in the drawing, by way of example only, is normally closed by a spring member closing contacts 44 (Fig. 2). Said spring member 45 may be tripped so as to open the contacts 44, to

reak the circuit, as, for example, by lever 46 pivoted in bracket 4'1 and normally held by the spring 45 in the inoperative position shown in Fig. 2. It will be apparent that if the free end of lever 46 is rotated toward the contacts 44, the spring 45 will be bowed to displace the same from one of the contacts, thereby breaking the circuit. The description of the switch 43 is merely by way of example, it being apparent that any other switch which may be opened upon engagement by the unit of the invention may be used, within the spirit and scope of the instant invention.

Pursuant to the invention, a cam member 23 determines the defrosting time and interval. The cam engages the lever 46 at a time predetermined by the circumferential position of member 22 on member H! (as indicatedby the position of the pointer 36 of the knob 3'6 on time setter dial) and for an interval predetermined by the circumferential position of the member 26 on member 22 (as indicated by the position of pointer 39 of member 26 on the interval face 40 of the knob 36).

The motor driven shaft 20, in a convenient commercial form, is a stub shaft. An elongated shaft might be substituted therefor, but it is convenient to utilize the conventional form of stub shaft 20 and to provide an extension therefor in the form of a shaft extender tube l9 longitudinally slitted as at HM and frictionally fitted onto or otherwise secured to the stub shaft 20. The term shaft, as used in this specification and in the appended claims, is defined to mean the shaft 20 per se or an elongated shaft or the shaft 20 and its extender I 9. The primary timesetter 22 frictionally engages the shaft to normally remain in circumferential registry with the shaft for rotation in unison therewith, but it may be readily slid around to a different position on the shaft by the user, for time-setting purposes.

The shaft has slitted portions l9?) which may snap past the free end22' of the member 22 to preclude accidental axial displacement of the parts. The knob 36 is secured to or formed integral with the upper end of the time-setter tube 22. The cam 23 is pivotally secured to the time-setter tube 22, as indicated at 24 in Fig. 6, for rotation in unison therewith, said cam member having an inner recessed face 25 to receive the member 22 and an outer interval face 35.

The structure described enables the user to predetermined and set the defrosting time by rotating the knob 36 so that the cam 23 will be so disposed on the shaft 20 as to be brought into registry with the lever 46 to break the circuit at the hour of each day desired-fixed by the registry of pointer 36' on the dial 38. The cam 23 may be displaced on the member 22 so that the defrosting interval may be likewise predetermined.

In the position shown in Fig. 10, the cam is so disposed that the outer face 35 thereof is substantially concentric with the center of the shaft. On rotation of the shaft, the outer cam surface 35 will then not be projected substantially radially of the center of the shaft beyond a circumferential path 50 cut by the free end of lever 46; in that position of the parts, the cam face 35 of the cam will engage and displace the lever 46 during each revolution of the shaft to open the switch 43 only for a short interval. In the position shown in Fig. 9, the cam has been substantially displaced radially so that a substantial portion of the outer face 35 thereof projects beyond the circumferential path 50; thus, the lever 46 will be displaced to open switch 43 for a longer period of time.

The extent of projection of the outer 'face 35 of the cam through path 50 is regulated by the position of interval setter 26 on the member 22. This may be fixed by providing the members 26 and 22 with interengaging means adapted to be set by the user. In the example shownin the drawings, the member 26 has an axial bore 21 and slots 28 and 29 so that it telescopically and frictionally engages member 22. It is provided with a flanged head which may be grasped by the user to slide member 26 axially on member 22 to the degree required to withdraw its pin 3| from aperture 32. The member 26 is rotated to register the pointer 39 with the desired time designation on the face 4|] of the knob 36 and member 26 is then moved axially downwardly on the member 22 so that the pin 3| will register with an aperture 32 in the member 22. This will fix the member 26 on the member 22 for rotation in unison therewith, completing two settings-firstly, the time at which the defrosting cycle will occur or be initiated, indicated by the position of pointer 36 of the knob on dial 38; secondly, the defrosting interval, indicated by the position of pointer 39 on face 40 of the knob 36.

The device, once set, will operate automatically to defrost the refrigerator at the same time and for the same interval of each cycle of rotation of the shaft. At the same time, the user may readily vary the time and/or interval by adjusting the device as indicated above. It will be apparent that the arrangement of the pin and recess means 3|, 32 may be altered and the members 22 and 26 may be provided with other complementary interengaging means substituted to that end, within the scope and purview of this invention, and that corresponding changes may be made in other parts described in the light of the disclosure herein without departing from the spirit and scope of the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A control timer adapted for application to a shaft rotating to complete a predetermined time cycle at each revolution, said shaft being disposed adjacent a switch to be controlled by the timer, comprising a time setter tube adapted to be positioned on said shaft and normally frictionally engaging the same for rotation in unison therewith and slidable circumferentially relative to, for time-setting purposes, a cam connected to the said tube and movable in unison therewith, said cam having an outer face to engage said switch to open the same, and an interval setter telescopically engaging the tube, and having an outer face for engagement with the cam to displace the latter, to thereby predetermine the interva1 of engagement of the switch by the outer face of the cam.

2. In a control timer as set forth in claim 1, complementary interengaging means on the interval setter and time setter tube to key the same for rotation in unison.

3. In a control timer as set forth in claim 1, complementary pin and aperture means on the interval setter and time setter tube to key the same for rotation in unison.

4. In a control timer as set forth in claim 1, a flanged portion on the interval setter to facilitate axial movement of the same on the time setter tube.

5. Ina control timer as set forth in claim 1, a knob secured to said timer tube, said knob having a pointer for registry with a time setter dial.

6. In a control timer as set forth in claim 1, a knob secured to said timer tube, said knob having a face provided with time markings, and 'a pointer on said interval setter for registry with said face.

'7. In a control timer as set forth in claim 1, said interval setter being slitted to frictionally and telescopically engage the time setter tube.

5 6 8. In a control timer as set forth in claim 1, Number Name Date means engaging the time setter and cam for ad- 470,184 Ebi Mar. 8, 1892 justing the position of the cam on the time setter. 593,066 Ball et a1 Nov. 2, 1897 JOSEPH A. DARWIN. 733,220 Krebs July 7, 1903 5 868,086 Hanson et a1. Oct. 15, 1907 REFERENCES CITED 1,127,398 Brown Feb. 9, 1915 The following references are of record in the 1,742,052 Day 31, 1929 file of this patent: Biendlct g 1 I owie 111g. UNITED STATES PATENTS 0 2,334,513 Shaw Nov, 16, 1943 Number Name Date 2,382,849 Bennett et a1 Aug. 14, 1945 118,873 Montfort Sept. 12, 1871 2,438,202 Burns Mar. 23, 1948 

